For example, Patent Literature 1 discloses a semi-trailing suspension device 3 that is divided in advance into a trailing arm 1 and a lower arm (one piece arm) 2 as shown in FIG. 9A. In the suspension device 3, a vehicle rear side end 1a of the trailing arm 1 and a vehicle width direction outer end 2a of the lower arm 2 are hinge-coupled by two rubber bushes 4a, 4b.
A vehicle front side end 1b of the trailing arm 1 is attached to a vehicle body via a trailing bush 5 in a turnable manner. A vehicle width direction inner end 2b of the lower arm 2 is attached to the vehicle body via a trailing bush 6 in a turnable manner. In this case, a semi-trailing axis A1 (see dotted and dashed thin line) with respect to the vehicle body is formed by connecting a turning center point C1 of the trailing arm 1 to a turning center point C2 of the lower arm 2 with each other.